The methods and knowledge of physics comprise three domains, viz., an empirical one with experimental and inductive methods, a theoretical one with predominantly deductive methods, and the relations between theory and experience with the methods of consistent adjustment. The experimental methods establishing the empirical basis will be described in detail. This empirical basis consists, among other things, of reproducible events and representative objects instead of unspecified things and direct perceptions. The dissimilarities between empirical and theoretical methods of concept formation are elaborated and contrasted with each other. Theoretical orders are defined as the conceptual representation of structures of reality and as the epistemological kernel of reality cognition in physics. In this context, it will be shown that Newtonian mechanics is not a causal theory. The diverse meanings and uses of models in physics are classified and discussed in detail.